Determination of the decarburation depth

Presentation for participants

Reference of the ILC: DC19LS
References of test methods: ISO 3887  ASTM E1077          
Frequency: Each year
Time schedule:  
Opening date of registrations Registration deadline Date of shipment of samples Start of the tests Deadline for carrying out the tests and providing the results Date of delivery of reports
15/12/2018 15/03/2019 20/05/2019 01/06/2019 15/07/2019 15/10/2019
Note: After the deadline, registrations are only accepted within the limit of availability of samples
Main characteristics d₁ (total decarburization), d₂ (functional decarburization), d₃ (partial decarburization), d₄ (global decarburization)
Other characteristics Surface carbon content, heart carbon content, surface hardness, heart hardness
  Caution: The number of determinations may be low for the secundary characteristics, what may make inefficient the comparison between laboratories
Determination of the assigned values (“true values” for each characteristic): By statistical computation of the totality of the results with possible selection on competence criteria (accreditation, validation by a reference body, quantity of tests performed in the year), test to detect possible collusion, merging of results not obtained in reproductibility conditions, suppression of technically unvalid results.
Type of statistical computation: Results are numerical. For each characteristic selected by the participant, 2 results shall be provided for each sample. The statistical computation will provide an assigned value with its attached uncertainty, values of standard deviations for repeatability, for reproductibility and for inter-sample homogeneity, limits of alerts for bias and repeatability of the participant, indiviual values for uncertainty of results of participants.
Number of samples per participant: 6
Product submitted to tests: Low alloyed steel
Type of samples: Discs
Approximate dimensions of samples: Ø40x50 mm
Specific preparation to be performed by the participant:  Preparation of surfaces of observation
Special notice for this ILC: Determinations of d₁, d₂, d₃, d₄ can be performed with the 3 methods : metallographic, chemical and/or hardness